Thermal radiation facelift device

ABSTRACT

A device is described that can be used by surgeons to provide quick and accurate face-lifting maneuvers that minimize the amount of tissue that has to be removed. The device comprised of a hollow undermining shaft with specially designed tip that can safely separate tissue planes and lyse fibrous tissue. Thermal radiation can be delivered down the shaft to heat and cause tissue contraction. The device can also include a temperature sensor that can be used to control the thermal radiation. Optionally, the device can also use ultrasound or electro surgical energy to improve tissue lysing.

This application is a continuation-in-part of U.S. patent applicationSer. No. 09/085,948, filed May 28, 1998 is now U.S. Pat. No. 6,203,540,incorporated herein by reference. This application is a divisional ofU.S. patent application Ser. No. 09/588,436 filed Jun. 6, 2000 is nowU.S. Pat. No. 6,391,023.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a surgical device for performing face-liftingusing thermal radiation, and more specifically to a face-lifting devicewith a specialized tip design that delivers heat. The invention providesa surgical device that can improve the accuracy and speed of face-liftoperations. Use of the present invention controllably causes thermallyrelated healing contraction of the target tissues thus allowing facelifting in younger patients without the removal or cutting-out of skinin properly selected patients. The use of the present invention may alsoaid in the performance and results of traditional face lifting involvingthe cutting out of skin.

2. Description of Related Art

Cutting (in surgery) will be defined as relatively cleanly breakingthrough similar or dissimilar tissues with minimal adjacent tissuetrauma and thus little tissue stretching, tearing or ripping. Lysis (insurgery) will be defined as breaking through similar or dissimilartissues with or without adjacent tissue trauma and may involvestretching, tearing or ripping. Depending upon the tissues lysed, thedegree of stretching or tearing of lysed tissue edges may beinconsequential or may even result in a desirable benefit such as postsurgical contraction. Planes of tissue are not often flat and representthe curviform intersection of dissimilar tissues and are made at leastpartly of fibrous tissues, either loose and spongy or firm and tough.Planes between the soft internal organs are usually loose and spongy.Planes of tissues in the face and on bones are firm and tough.Undermining will be defined as tissue separation either within orbetween defined tissue planes. Undermining may be by sharp (instrument)or dull (instrument) depending upon the amount of fibrous tissue bindingor existing between the tissue planes to be separated. Undermining isusually performed, as is most surgery, with the intention of minimizingtrauma. Sharp instrument undermining is usually performed to separatehighly fibrous or collagenous tissues; however, sharp underminingsuffers from the risk of penetrating adjacent tissues inadvertentlybecause of loss of ability to follow the desired plane. Inability tofollow or maintain the plane in sharp undermining is frequently due tolimited visibility, difficulty “feeling” the fibrous plane, or scarring(collagen fibrosis) resulting from previous trauma or surgery. Evenexperienced surgeons may from time to time lose the correct plane ofsharp undermining; great skill is required. Blunt undermining allows arounded, non-sharp tipped, instrument or even human finger to find thepath of least resistance between tissues; once the desired plane isfound by the surgeon, it is easy to maintain the plane of bluntundermining until the task is complete. Unfortunately, blunt underminingbetween highly fibrous tissues such as those that comprise and maintainthe shape of the human face usually causes imprecise tunneling withfibrous walls of variable thickness. Dissection usually implies adeliberate and careful sorting out and identification of tissues andusually implies that some sort of undermining has been performed toisolate the desired structure(s). In face-lifting surgery, plasticsurgeons have so commonly used the terms undermining and dissectioninterchangeably that they have become synonymous for the most part inthis specific situation. Tracking means to maintain a direction ofmovement upon forcing a tissue-separating instrument withoutunpredictable movement or leaving the desired tissue plane(s). Planartracking means to stay in the same tissue planes. Linear tracking meansto move uniformly in a straight or uniformly curved path withoutunpredictable movement Groups of linear tracks may form a network thatcreates an undermined tissue plane.

Anatomical Perspective: Lysis or undermining in one dimension (linear=x)implies forming a tunnel. Lysing or undermining in 2 dimensions at anyone instant forms a plane (x, y). Traditional face-lift undermining isdone just under the leather (dermis) layer of the skin where dermisjoins underlying fat or subcutaneous (SQ). Even deeper within the SQ fatrun larger blood vessels and delicate, non-regenerating motor nerves tothe muscles that give the human face motion and expression. Deep/beneathto the SQ fat reside the muscles and glands of the face. The relevantface-lift anatomy may be referenced in Micheli-Pellegrini V., SurgicalAnatomy and Dynamics in Face Lifts, Facial Plastic Surgery 1992:8:1-10,Gosain A. K. et al., Surgical Anatomy of the SMAS: A Reinvestigation,Plast Reconstr Surg. 1993: 92:1254-1263 and Jost G, Lamouche G., SMAS inRhytidectomy, Aesthetic Plast Surg. 6:69, 1982. The SQ fat differs frombody location to body location. On the face, the SQ fat has manyfiber-bundles (septae) carrying nerves and blood vessels. If a surgeonwere to move, shove, or forwardly-push a blunt, dull-tipped, 1-inchchisel or pencil shaped device through the fat of the face where SQabuts the dermis, the sheer thickness of the fiber bundles would likelycause slippage of the device and result in the formation of pockets ortunnels surrounded by compacted fiber bundles or septae. Properperformance of a face-lift involves breaking the septae at a properlevel to avoid damaging more important structures such as blood vesselsand nerves and glands.

Disadvantages of the current techniques are numerous. Face-liftingdevices described in the prior art resemble undermining devices thatwere constructed with cutting edges that rely entirely on the skill ofthe surgeon to maintain control. Inadvertent lateral cutting or tissuetrauma is difficult to control. In addition, speed of separation isaffected to ensure accuracy by the surgeon in separating fibrous tissueplanes. There are two principle locations for face lift undermining(dissection): in the more common lower facelift (cheek/neck-lift)undermining in the subcutaneous tissues is customarily performed; in theless common upper facelift (which approximates brow-lifting) underminingin the subgaleal or temporalis fascia plane is customarily performed.Use of prior art undermining devices (including scissors, sharprhytisectors, etc) in these planes during cosmetic surgery has, attimes, resulted in unwanted cutting, trauma or perforation of adjacentstructures. Scissors and rhytisectors are planar cutting instruments;thus, the position of the cutting edges with respect to the surface ofthe face is controllable only by the surgeon estimating location, as no3^(rd) dimensional bulbous limitation exists. Unfortunately, scissorswith 3 dimensionally “bulbous”, rounded tips cannot close all the way tocut target tissue. Scissors with 2 dimensionally rounded tips can closeall the way to cut target tissue but may wander inadvertently betweentissue planes due to the thin third dimension (thickness) of thescissors blades.

Rubin (U.S. Pat. No. 3,667,470) describes a bone shaver and groovingdevice that consists of a single sharp edged extension protrudingperpendicular to the plane of motion of the cutting edge of the device.The extension is intended to carve and maintain a groove in rigid,immobile, bone as it is driven forward by a surgeon's hammer. Thisdevice is impractical for lysing facial planes because the extensionwould severely damage blood vessels and delicate nerves. In addition,Rubin's invention would not maintain a planar track in soft tissues.Hendel (U.S. Pat. No. 4,600,005) describes a guided osteotome forharvesting cranial bone graft that has a single cutting tip between twobulb like guides at the edges. The guides prevent the hammer drivencutting edge from penetrating the skull too deeply as the harvestingcutting edge would tend to “dive” deep into the skull toward braintissue if unhindered (vertical tracking control). However, these singleguides with their geometry cannot effectively compress or pass throughthe collagenous, fibrous tissues into recessions making for a moreprecise lysis of the grouped fibers and bundles.

Current face-lifting instruments that cut with other than manual energydo not address the novel concept of a “protected plane” during energizedface-lifting dissection. Current lasers must be fired from positionsoutside the patient to energize tissue within the face to cut in a veryimprecise fashion (See “Manual of Tumescent Liposculpture and LaserCosmetic Surgery” by Cook RC and Cook KK, Lippincott, Williams, andWilkins, Philadelphia ISBN: 0-7817-1987-9, 1999). Tissue is damaged withlittle control. Current electro-surgical devices for facelift tissueenergizing must be delivered through large open pockets or through thelimited access and slow moving, tedious endoscopes. Farin (U.S. Pat. No.5,776,092) describes a single tube device that can deliver laser,ultrasound or radio frequency devices to treat tissue. However, Farin'sdevice is not intended for separating tissue planes and is susceptibleto catching, tearing or puncturing the tissue when manipulated. It wouldbe advantageous to provide a safe technique and device for the preciseapplication of energy to properly separate and heat facial tissue whilemaintaining an exact distance from the delicate surface of the skin. Theideal device achieves this function while minimizing the chances ofcollateral damage to vital structures such as nerves and delicatevessels. It would be additionally advantageous for the same provisionsto allow for a uniform forward tracking and feel of motion of the devicethat provides a surgeon with instantaneous knowledge. Properly sized andplaced protrusions and recessions address all of these problems in amanner not previously possible.

One of the most recent competing procedures to incompletelydissect/lyse/cut a face-lift plane is traditional or ultrasonicliposuction. Unfortunately, dissection is incomplete as the cannulasonly make tunnels. The tissues between the tunnels must be cut withscissors in order to create a plane. When the scissors cuts the fibertissues and blood vessels constituting the walls of the tunnels,bleeding and trauma occur and frequently require spot coagulation undervisualization. Other severe drawbacks of the incomplete undermining thatliposuction cannulas perform include the common trauma and resultantmouth droop paralysis that occurs in the hands of even prominentsurgeons when the delicate and anatomically unpredictable (20% of thepopulation) marginal mandibular branch of the facial nerve is cutAdditionally, ultrasonic cannulas become hot and can cause thermal burnscalled “end hits” when the cannula tip is thrust against the inside ofthe skin as is common during the procedure.

Just as sharp undermining or dissection has its disadvantages, aspreviously mentioned, blunt dissection suffers from its own difficultiesas well. Forcing a blunt object through tissue avoids indiscriminatesharp cutting of important structures (nerves, vessels). Bluntundermining compacts the stronger, firmer, strands of collagen evencontained within tissues as soft fat into thicker “bands” (some overlythick for uniform cutting). Undesirably for a face-lift, traditionalblunt object undermining may indiscriminately force aside and compactseptae causing incomplete lysis or freeing of the tissues. Alsounfortunately for face lifting, traditional purely blunt objectundermining will result in random motion or uncontrollable-slippage ofthe underminer tip on forward motion and thusly loss of precise trackingof the underminer through target tissue.

Currently it takes surgeons between 20 minutes and one hour to carefullyand properly dissect/undermine/lyse/lift a lower face. It usually takesbetween 10 minutes and 30 minutes, depending upon the patient tocarefully and properly spot coagulate/seal all of the blood vessels thatwere cut during the aforementioned lysing portion of the face-lift. Forupper face lifting, times are less than half that mentioned for lowerface lifting. The present invention would reduce time for a surgeon todo both the duties of lysing and coagulation since the device performsboth tasks as well as aids in maintaining proper positioning andtracking. The time reduction should be at least 50-75%. Reducedoperating time means less time a wound is open to potential infection,lowered surgical costs and less time and therefore less risk underanesthesia and thus a general improvement in the procedure.

There exists a special subset of the general population that may benefituniquely from the present invention. Men and women between the ages of35 and 55 are just beginning to droop and develop folds. However, thereis not as much undulating wrinkling as in older patients. Currently longincisions of 10-20 cm are made around each of the two ears, for thepurposes of hiding the scars. Skin is cut out and discarded and theremaining skin stretched. Unfortunately, skin does not thicken inresponse to stretching; it only thins. Unfortunately, some plasticsurgeons in the early 1990's advocated “prophylactic” or “preemptive”face-lifting on women in their 40's purportedly to “stay ahead ofnature.” This philosophy has now been discounted and discredited by thevast majority of reputable experts. With the present invention,tightening will be most dramatic in younger patients between 35 and 55years of age such that surgeons may not have to cut out or stretch skinfor a desirable effect for most patients in this population. In thiscase, the present invention is inserted through only 3 relatively smallincisions of less than 1 cm each and energy is applied to the uppersubcutaneous, lower dermal and platysmal face-lift layers. If the 3small incisions can be used and no skin excised, then the procedure willtake less than 15 minutes following anesthesia and the effects will lastfor at least several years.

Given the disadvantages and deficiencies of current face-liftingtechniques, a need exists for a device that provides a fast and safealternative.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method and a devicethat can be used by surgeons to provide quick and accurate face-liftingmaneuvers that minimize the amount of affected tissue.

It is another object of the present invention to provide an underminingdevice that can position lysing surfaces at a proper level for fibroustissue lysing during a face-lift.

Another object of the invention is to provide quick and accurateface-lifting maneuvers.

Still another object of the invention is to provide a surgicalface-lifting device that easily maintains the proper dissection plane.

It is a further object of the invention to provide a surgicalface-lifting device that easily maintains the proper dissection planewhile lysing and delivers thermal radiation to the internal collagenoustissues of the face to induce skin tightening.

Other objects of the invention will be apparent from the disclosureherein.

Thermal effects to the collagenous (dermal, superficial platysmamusculature and other) tissues of the face in the facelift plane cancause cosmetically desirable contraction of the dermal tissues withbeneficial tightening of the facial tissues. The present inventioncombines a unique lysing design with means for providing thermalradiation to efficiently lyse and simultaneously induce the thermalcontraction necessary for face lifting. The present invention may beused in hospitals as well as office-based surgery and minimizes pain andrisk of injury.

The device is comprised of an undermining shaft with a special tip thatcan be easily positioned between dissection planes in tissue and thenmanipulated to separate tissue planes and lyse fibrous tissue. A thermalsource and delivering means delivers energy to the distal end of theshaft. A temperature sensor monitors the tissue temperature, and controlelectronics process temperature information to control the thermalradiation for optimum tissue contraction. An optional secondary lightsource that is visible to the surgeon can be used to help visualize thelocation of the thermal radiation exit window. Optionally the device canalso use ultrasound energy or lower frequency vibrational energydelivered down the shaft to improve tissue lysing.

In one embodiment of the invention, the user sets the desired tissuetemperature on an external control unit using a touch pad or other userinterface. The shaft of the device is then inserted through a small (˜1cm long) incision and positioned at the desired tissue plane. For lowerface lifting the surgeon incises the skin in front of the ears and underthe chin. Force is then applied to the shaft of the device by the usershand to separate tissue planes while excluding critical structures(nerves, vessels) thus avoiding entanglement or trauma or indiscriminatecutting of these important structures. The same protrusions that excludecritical structures by virtue of their relationship to the recessedcutting segments also serve to position the depth of the presentinvention with respect to the lower dermis. The spacing of theprotrusions (bulbs) and recessions (lysing segments) maintains thetracking of the instrument. Tracking is instantly palpable by thesurgeon and requires no monitor to know how the device is moving. Boththe number and spacing of protrusions in the present invention reducewobble or lateral (horizontal) slippage during forward thrusting of theshaft. Uniquely, vertical slippage is prohibited as well. The width ofthe protrusions/bulbs maintains the correct distance between the lysingsegments and the delicate underside of the superficial skin or dermis.The tip of the device and the action of the device can befelt/appreciated without direct visualization (endoscope). The surgeoncan palpably feel the device is tracking in the proper location. Thefeel of the device as it moves with palpable and easily grade-ableresistance through the facial tissues can immediately tell theuser-surgeon the location and the amount of undermining that hasoccurred at that location.

The unique tip is comprised of alternating, preferably relativelysymmetrical-across-a-midline, protrusions and recessions. Theprotrusions can be bulbous, geometric, etc., as long as the tips of theprotrusions are able to push and compress tissues into the cuttingrecessed segments. The recessed segments have a sharpened edge thateffectively lyses the tissue that comes into contact as the device ispushed forward. The close spacing of the grooves (caused by thealternation of tip protrusions and recessions) provides the user with afeel during forced tissue movement and significantly limits slippage.Again, the tip of the device, and the action of the device can befelt/appreciated without direct visualization (endoscope).

If desired by the user, thermal radiation exits an optical window nearthe distal end of the shaft to heat the tissue that lies near thewindow. The thermal radiation propagates away from the face toeffectively heat the skin layer from the inside out The purpose of thethermal energy is to alter/irritate the collagen so as to controllablycause later shrinkage and optionally to control any bleeding. The powerrequired to coagulate such a layer of tissue is only a few watts. Thisflux can be provided by a thermal source such as a hot tungsten filamentwith temperature of about 1000 degrees. Since most preferred thermalsources are not highly visible to the human eye, the device will offerthe user the option to simultaneously transmit visible light down theshaft to give the user the ability to visualize the region beingtreated. For example, red light that is easily transmitted throughseveral millimeters of skin could be safely used to guide the surgeon.Thermal radiation can be controlled manually by the user oralternatively automatically controlled to prevent excessive orinappropriate thermal damage.

An alternative embodiment of the device uses a heated segment near thedistal tip of the device to heat the tissue directly. The heated segmentcould be a thin film resistor that is heated by flowing a currentthrough the film. The temperature of this film would be selected by theuser and will typically be less than 80° C. This embodiment eliminatesthe possibility of the tissue being heated above the desiredtemperature. In addition, the heated segment can be larger than thethermal radiation output window in previous embodiments withoutsignificant risks.

In one embodiment, the temperature of the target tissue is measured witha non-contact temperature sensor and the value displayed and used by thethermal radiation control unit to actively control the thermalradiation. The preferred temperature sensor would be an infraredtemperature sensor, but other conventional sensors may be used, such asfiber optic fluorescence temperature sensors, thermal resistancesensors, and thermocouple sensors.

In order to improve lysing efficiency, one embodiment of the deviceincorporates an ultrasound transducer into the hand piece that transmitsultrasound energy down the shaft. A lower frequency vibrating transducercould also be incorporated into the device to improve lysing.

In another embodiment, the recessed cutting segments of the device aredriven by an electro-surgical RF generator to improve lysing and allowRF heating of tissue.

The present invention can be used to improve the efficacy and safety offace lifting and is thus useful in a variety of cosmetic procedures. Theforgoing and other objects, features, and advantages of the presentinvention will become apparent from the following description andaccompanying drawings.

The disclosures of this publication and the disclosures of all otherpublications recited herein are incorporated by reference as if fullyset forth herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and form part ofthis disclosure, illustrate embodiments of the invention and togetherwith the description, serve to explain the principles of the invention.

FIG. 1 shows present invention (and partial top view of face liftapparatus) in use.

FIG. 2 shows a side view of face-lift apparatus attached to articulatingarm or fiber optics.

FIG. 3 shows top view of face-lift apparatus attached to articulatingarm or fiber optics.

FIG. 4 shows off-center frontal view of tip of face-lift apparatusprotrusions and recessions.

FIG. 5 shows a cross-sectional view of the distal tip showing a compactthermal source for heating tissue.

FIG. 6 shows a cross-sectional view of an alternative embodiment of thepresent invention that contains the thermal source in the handpiece.

FIG. 7 shows a cross-sectional view of face-lift apparatus that uses ahot surface to heat tissue.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a device that can be used by surgeons toprovide quick and accurate face-lifting maneuvers that minimize theamount of tissue that has to be removed. The device is comprised of anundermining shaft that can be easily positioned between dissectionplanes in tissue and then manipulated to separate tissue planes and lysefibrous tissue, a means for heating tissue near the distal end of theshaft, a temperature sensor that monitors the tissue temperature, andcontrol electronics that process temperature information to control thethermal radiation for optimum tissue contraction. An optional secondarylight source that is visible to the surgeon can be used to helpvisualize the location of the thermal radiation exit window. Optionally,the device can also use ultrasound energy delivered down the shaft toimprove tissue lysing.

FIG. 1 shows a partial top view of an embodiment of the face-liftapparatus 10 of the present invention as it is being used. The handle 6is gripped in the hand 12 of the user of the device. The shaft 4 withthe special lysing tip 2 is inserted through an opening 8 at a suitablelocation on the face of a patient. Dashed lines indicate the portion ofthe device hidden from view under the skin. Curved stretch lines 3indicate the upward force applied on the device 10 and therefore shaft 4and the overlying skin of the face. The apparatus may then be thrustforwardly while lifted forcefully by the operator to perform itsfunction and maintain the plane of undermining. Window 50 (dashed andhidden from clear view in this representation) allows thermal radiationto escape from within the shaft 4.

FIG. 2 is a side view of the face-lift apparatus 10. The tip 2 may beslightly larger than the shaft 4. The tip 2 can be a separate piece thatis secured to shaft 4 by a variety of methods such as a snap mechanism,mating grooves, plastic sonic welding, etc. Alternatively, in this modeltip 2 can be integral or a continuation of shaft 4 made of similar metalor materials. The tip 2 may also be constructed of materials that areboth electrically non-conductive and of low thermal conductivity; suchmaterials might be porcelain, ceramics or plastics. Portions of the tipand shaft may be covered with Teflon to facilitate smooth movement ofthe device under the skin. An optional electrically conductive element61 may be provided to bring RF electro surgical energy to metal orelectrically conductive elements mounted in the recessions (see FIG. 3).The shaft 4 is tubular in shape or can be a somewhat flattened tubeoblong in cross section. The shaft 4 is made of metal with a hollowinterior that can contain insulated wire or wires 61. Alternatively, theshaft 4 may be made of plastic that will act as its own insulation aboutwire or electrically conductive element 61. The optional electricallyconductive element 61 internal to shaft 4 conducts electrical impulsesor RF signals from an optional external power/control unit (such as aValleylab Surgistat, Boulder, Colo.). An optional temperature sensor 35placed near the distal tip of the shaft is used to monitor the localtemperature. This information can be used by the control electronics tocontrol the energy delivered to the tip. An ultrasound transducer 32 canalso be activated to transmit energy to the tip 2 and provide additionalheating and improve lysing.

FIG. 3 is an enlarged plan or top view of the tip 2 as used in upperface-lift. This tip 2 shows four protrusions 26 and three recessions 28.The groove created by the tapering recessions may be up to onecentimeter in length. The width of this tip varies between 12 mm to 20mm and the thickness varies between 3 mm to 4 mm. Optical window 50allows thermal radiation to exit the shaft and irradiate tissue directlyabove the window. The user can enable or disable the thermal sourcethrough a hand or foot switch (not shown).

FIG. 4 shows an off-center frontal view of the tip of the face-liftapparatus protrusions and recessions. The tip 2 has four protrusions 26and three recessions 28 in which are seated electrodes 81. The RFelectrodes 81 located at the most proximal portion of the cuttingrecessions can increase lysing and coagulation at the cutting edge. TheRF electrodes 81 are connected by conducting wires 61 (FIG. 2) to thepower/control unit The user can enable or disable the RF power through ahand or foot switch (not shown). Window 50, allowing egress of thermalradiation and temperature sensor 35 are also located on the tip and maybe of varying sizes. The width of this tip varies between 5 mm and 10 mmwhile the thickness may vary between 2 mm to 4 mm. The tip, however, isnot constrained by those dimensions. FIG. 5 shows a cross sectional viewof an embodiment of the face-lift device 10 of the present invention.The shaft 4 with the special lysing tip 2 is inserted through an openingat a suitable location on the face of a patient. The apparatus may thenbe thrust forwardly while lifted forcefully by the operator to performits function and maintain the plane of undermining. A hot filament 13within the device is heated by flowing current through connecting wires65. The filament 13 is held rigidly in position within the paraboliccavity by the strength of the wire 56. Alternately, the filament 13 isfixedly attached to the shaft 4.The hot filament 13 emits optical andthermal radiation 45 that can directly exit window 50 or be reflectedoff a reflector 14 to also exit through window 50. The reflector 14 canhave a parabolic shape to effectively collect all optical and thermalradiation emitted away from the window 50. The hot filament 13 can be atungsten carbide filament similar to those used in high power lightbulbs. The wavelength may be adjusted and controlled by adjusting thefilament temperature/current The window 50 can be selected from a widevariety of glass that transmits optical, near infrared and infraredlight (e.g. quartz, fused silica and germanium.) The tissue penetrationdepth depends on the wavelength of the light (e.g., 1 μm penetratesthrough 10 mm, 10 μm penetrates through 0.02 mm). The broad emissionspectrum from the hot filament 13 can be filtered by window 50 toachieve the desired tissue effect. In particular filtering the emissionspectrum to heat the dermis to temperatures of approximately 70° C. willcause the desired collagen shrinkage and tightening. The optimumspectral filtering depends on skin thickness and structure._Atemperature sensor 35 connected to the control unit by electrical wire67 monitors the temperature of tissue that is in contact with the shaft4. In order to eliminate excessive heating of the shaft 4 and thesurrounding facial tissue, the heating element 13 and reflector 14 arethermally isolated by low thermal conductivity materials. The heatingelement is isolated by not touching the shaft, whereas the reflector canhave an isolating layer where it attaches to the shaft. In addition,cold nitrogen gas can be injected through tube 70 and pumped out throughthe hollow shaft to cool the tip 2 and shaft 4. Flowing nitrogen gasthrough the hollow shaft also reduces oxidation damage to the filament.

FIG. 6 shows an alternative embodiment of the present invention thatreduces the thermal load to the shaft 4 and eliminates the need for highelectrical currents within the shaft In this embodiment the hot filament13 is located in the handle 20 of the device and is connected to thepower unit by wires 65 and cable 75. The optical and thermal radiation45 is transported through the hollow wave-guide within the shaft 4 andreflected off the mirror 16 through the window 50. The absorptioncoefficient within the wave-guide is inversely proportional to the cubeof the height of the hollow wave-guide within the shaft and can be madesmall for the hot filament 13 when operated at temperatures greater than600 degrees. The absorbed energy would be evenly distributed over theentire shaft 4 and the average temperature increase would be small. Amirror reflector 14 redirects radiation emitted away from the shaft downthe shaft to improve overall system efficiency. A temperature sensor 35connected to the control unit by electrical wire 67 and cable 75monitors the temperature of tissue that is in contact with the shaft 4.The ability to continuously monitor the temperature greatly reduces thedanger of overheating and tissue carbonization. In addition, coldnitrogen gas can be injected through tube 70 to cool the tip 2 and shaft4. The nitrogen gas can exit through the handle 20 or be recirculatedthrough a cooling system. Flowing nitrogen gas through the hollow shaftalso reduces oxidation damage to the filament. A cable 80 connects thepresent device to the control/power unit.

FIG. 7 shows an alternative embodiment of the present invention in whichtissue heating is achieved by the direct contact with a hot surface 55.In this embodiment electric current flowing through wires 65 heat aresistive load 55 to a user selected temperature. For most applicationsthe temperature will be less than 80° C. to induce collagen shrinkagebut prevent thermal collateral damage. This embodiment eliminates therisk that any tissue region can be heated above the desired temperatureby misuse. This allows the size of the hot surface 55 to be larger (e.g.several centimeters long, 1 centimeter wide) which can speed up theprocedure. In addition the hot surface 55 can be made up of multipleelements that can be set to different desired temperatures. Theresistive load could be a thin film resistor and the film temperaturecould be estimated from the measured resistance. Alternatively aseparate temperature sensor 35 can be placed close to the heatingelement The measured temperature is used by the control unit to controlthe current through the resistive load. In order to reduce heating tothe shaft 4 and tip 2, cold gas or liquid can be injected through tube70 and pumped out through the hollow shaft. The specific shape of theheater 55 and surface temperature can be adjusted to obtain the desiredtissue coagulation depth. Instead of a resistive load, the heatingelement could be the hot side of a Peltier thermoelectric cooler. Anadvantage of a thermoelectric cooler is that the opposite surface iscooled below ambient temperature. Single stage thermoelectric coolerscan achieve temperature differences of up to 40° C. By thermallyconnecting the cold surface of the thermoelectric cooler to the bottomof the shaft the cooler can be used to reduce heating of the shaft awayfrom the hot surface.

In all embodiments of the device the shaft can be coated with abiocompatible non-stick material such as Teflon® to reduce tissuesticking to the device during the procedure.

The foregoing description of preferred embodiments of the invention ispresented for purposes of illustration and description and is notintended to be exhaustive or to limit the invention to the precise formdisclosed. Many modifications and variations are possible in light ofthe above teaching. The embodiments were chosen and described to bestexplain the principles of the invention and its practical application tothereby enable others skilled in the art to best use the invention invarious embodiments and with various modifications suited to theparticular use contemplated.

What is claimed is:
 1. A method for performing skin surgery, comprisingseparating subcutaneous tissue from dermal tissue using a shaft having aproximal end and a distal end, wherein said distal end comprises aplurality of protruding members separated by at least one lysingsegment, wherein said lysing segment is recessed relative to saidprotruding members; and delivering thermal energy from said shaft to thetissue.
 2. The method of claim 1, wherein the separation of saidsubcutaneous tissue from said dermal tissue is at least partly carriedout by delivering ultrasonic energy to said distal end of the shaft. 3.The method of claim 1, wherein the separation of said subcutaneoustissue from said dermal tissue is at least partly carried out bydelivering radio frequency energy to an electrode in at least onecutting segment of said lysing segment.
 4. The method of claim 1,further comprising monitoring the temperature at the distal end of theshaft.
 5. The method of claim 1, further comprising controlling thetemperature at said distal end by controlling the delivery of saidthermal energy.
 6. The method of claim 1, further comprising monitoringthe transmission of visible light through the skin to determine thelocation of the device.